Electronic device and heat dissipation module thereof

Abstract

An electronic device. The electronic device comprises a heat source, a housing having an inlet and an outlet, a fan disposed in the housing and selectively rotating at a first speed and a second speed higher than the first speed to generate air flow in the housing to cool the heat source, and a plurality of louvers disposed on the housing, having adjustable angles and selectively positioned at a first angle and a second angle. When the louvers are positioned at the first angle, the fan rotates at the first speed, and when the louvers are at the second angle, the fan rotates at the second speed.

1. A projector, comprising:
 a light module; 
 a housing having an inlet and an outlet; 
 a fan disposed in the housing and selectively rotating at a first speed and a second speed to generate air flow in the housing to cool the light module; and 
 a plurality of louvers disposed on the housing to prevent light leakage, having manually adjustable angles and selectively positioned at a first angle and a second angle, wherein the air flow flows out of the housing through the louvers of the outlet when the fan operates, and when the louvers are positioned at the first angle, the fan rotates at the first speed, and when the louvers are at the second angle, the fan rotates at the second speed, and when the first angle is smaller than the second angle, the first speed is higher than the second speed; and 
 wherein the first and second angle are measured between a cross-sectional plane of the outlet and a side of each of the plurality of louvers. 
 
     
     
       2. The projector as claimed in  claim 1 , wherein the louvers are adjacent to the inlet. 
     
     
       3. The projector as claimed in  claim 1 , wherein the louvers are adjacent to the outlet. 
     
     
       4. The projector as claimed in  claim 1 , wherein the angle of the louvers is adjusted manually, and when the angle of the louvers is changed, the speed of the fan is changed. 
     
     
       5. The projector as claimed in  claim 1 , wherein when the louvers are positioned at the first angle, a first flow resistance is generated in the housing, and when the louvers are at the second angle, a second flow resistance is generated in the housing, less than the first flow resistance. 
     
     
       6. The projector as claimed in  claim 1 , wherein when the fan is stopped, the louvers generates a maximal flow resistance in the housing. 
     
     
       7. The projector as claimed in  claim 1  further comprising a control unit electrically connected to the fan and the louvers, wherein when the louvers are at the first angle, the control unit drives the fan to rotate at the first speed, and when the louvers are at the second angle, the control unit drives the fan to rotate at the second speed. 
     
     
       8. The projector as claimed in  claim 7 , wherein the angle of the louvers is adjusted manually, and when the angle of the louvers is changed, the control unit changes the fan speed. 
     
     
       9. The projector as claimed in  claim 7 , wherein when the fan is stopped, the control unit drives the louvers to generate a maximal flow resistance in the housing. 
     
     
       10. The projector as claimed in  claim 7 , wherein when the louvers are at the first angle, a first flow resistance is generated in the housing, and when the louvers are at the second angle, a second flow resistance is generated in the housing, less than the first flow resistance. 
     
     
       11. The projector as claimed in  claim 1 , wherein the fan is disposed near the inlet. 
     
     
       12. A projector, comprising:
 a light module; 
 a housing having an inlet and an outlet; 
 a fan disposed in the housing and selectively rotating at a first speed and a second speed to generate air flow in the housing to cool the light module; and 
 a plurality of louvers disposed on the housing, having manually adjustable angles and selectively positioned at a first angle and a second angle, wherein when the louvers are positioned at the first angle, the fan rotates at the first speed, and when the louvers are at the second angle, the fan rotates at the second speed, and when the first angle is smaller than the second angle, the first speed is higher than the second speed, and the air flow flows out of the housing through the louvers of the outlet when the fan operates; and 
 wherein the first and second angle are measured between a cross-sectional plane of the outlet and a side of each of the plurality of louvers. 
 
     
     
       13. The projector as claimed in  claim 12 , wherein the louvers are adjacent to the inlet or the outlet. 
     
     
       14. The projector as claimed in  claim 12 , wherein the angle of the louvers is adjusted manually, and when the angle of the louvers is changed, the speed of the fan is changed. 
     
     
       15. The projector as claimed in  claim 12 , wherein when the louvers are positioned at the first angle, a first flow resistance is generated in the housing, and when the louvers are at the second angle, a second flow resistance is generated in the housing, less than the first flow resistance. 
     
     
       16. The projector as claimed in  claim 12 , wherein the fan is disposed near the inlet. 
     
     
       17. The projector as claimed in  claim 12  further comprising a control unit electrically connected to the fan and the louvers, wherein when the louvers are at the first angle, the control unit drives the fan to rotate at the first speed, and when the louvers are at the second angle, the control unit drives the fan to rotate at the second speed. 
     
     
       18. The projector as claimed in  claim 17 , wherein the angle of the louvers is adjusted manually, and when the angle of the louvers is changed, the control unit changes the fan speed. 
     
     
       19. The projector as claimed in  claim 17 , wherein when the fan is stopped, the control unit drives the louvers to generate a maximal flow resistance in the housing. 
     
     
       20. The projector as claimed in  claim 17 , wherein when the louvers are at the first angle, a first flow resistance is generated in the housing, and when the louvers are at the second angle, a second flow resistance is generated in the housing, less than the first flow resistance.